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Theory and classification of mass extinction causation

National Science Review 2024年第1期11卷 16-36页

作者： Thomas j.Algeo jun Shen State Key Laboratory of Biogeology and environmental Geology China University of Geosciences—Wuhan State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences—Wuhan Department of Geosciences University of Cincinnati

Theory regarding the causation of mass extinctions is in need of systematization, which is the focus of this contribution. every mass extinction has both an ultimate cause, i.e. the trigger that leads to various climato-environmental changes, and one or more proximate cause(s), i.e. the specific climato-environmental changes that result in elevated biotic mortality. With regard to ultimate causes, strong cases can be made that bolide(i.e. meteor) impacts, large igneous province(LIP) eruptions and bioevolutionary events have each triggered one or more of the Phanerozoic Big Five mass extinctions, and that tectono-oceanic changes have triggered some second-order extinction events. Apart from bolide impacts, other astronomical triggers(*** flares, gamma bursts and supernova explosions) remain entirely in the realm of speculation. With regard to proximate mechanisms, most extinctions are related to either carbon-release or carbon-burial processes, the former being associated with climatic warming, ocean acidification, reduced marine productivity and lower carbonate δ13C values, and the latter with climatic cooling, increased marine productivity and higher carbonate δ13C values. environmental parameters such as marine redox conditions and terrestrial weathering intensity do not show consistent relationships with carbon-cycle *** this context, mass extinction causation can be usefully classified using a matrix of ultimate and proximate factors. Among the Big Five mass extinctions, the end-Cretaceous biocrisis is an example of a bolide-triggered carbon-release event, the end-Permian and end-Triassic biocrises are examples of LIP-triggered carbon-release events, and the Late Ordovician and Late Devonian biocrises are examples of bioevolution-triggered carbon-burial events. Whereas the bolide-impact and LIP-eruption mechanisms appear to invariably cause carbon release, bioevolutionary triggers can result in variable carbon-cycle changes, e.g. carbon burial durin

关键词： biocrisis ultimate cause proximate cause bolide large igneous province bioevolutionary event

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Mortality rate after total knee arthroplasty or total hip arthroplasty in patients with a history of liver transplant

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World journal of Orthopedics 2024年第4期15卷 310-311页

作者： e Carlos Rodriguez-Merchan Department of Orthopedic Surgery La Paz University Hospital-IdiPazMadrid 28046Spain

In this editorial I comment on the article by Ahmed et al published in a recent issue of the World j Orthop 2023;14:*** is well known that patients who have undergone a liver transplant(LT)may need to have a total hip arthroplasty(THA)or total knee arthroplasty(TKA)*** et al stated that the mortality rate in these patients was similar to the one of the general ***,there are three articles previously published that found higher mortality in LT patients who experienced THA/TKA than in the general population(individuals without LT).Therefore,in this editorial I would like to point out that there is controversy in the literature regarding whether LT patients undergoing THA/TKA have higher mortality than the general ***,future research should attempt to resolve this controversy.

关键词： Liver transplant Total knee arthroplasty Total hip arthroplasty Results Mortality

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Intracranial pressure is elevated at 24h post-stroke inmice

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Neuroprotection 2024年第1期2卷 60-64页

作者： Kirby e.Warren Rebecca j.Hood Fredrick R.Walker Neil j.Spratt School of Biomedical Sciences and Pharmacy University of NewcastleCallaghanAustralia Hunter Medical Research Institute NewLambton HeightsAustralia School of Biomedicine Discipline of Anatomy and PathologyFaculty of Health and Medical SciencesThe University of AdelaideAdelaideAustralia Department of Neurology John Hunter HospitalNewLambton HeightsAustralia

Background:It has long been assumed that post-stroke intracranial pressure(ICP)elevation occurs because of large infarct and edema ***,we have repeatedly shown IcP elevation at 24 h post-stroke in the presence of little to no edema in *** processes are often conserved across species and types of ***,we aimed to determine if an ICP rise occurs at 24 h post-stroke in the presence of small infarct and edema volumes in ***:Mice were randomized by random number table to either photothrombotic stroke or sham surgery(n=15).epidural ICP was recorded using a fiber optic catheter at 1 h post-stroke(baseline)and between 23 and ***:ICP was significantly higher at 24 h compared to baseline in stroke animals(n=6;10.71±6.45mmHg vs.3.74±2.20mmHg,respec-tively;p=0.03).ICP at 24 h was also significantly higher in stroke mice compared to sham(n=6;3.45±1.43mmHg;p=0.02).There was no change in ICP in sham mice(p=0.9).edema volumes in stroke animals were small(0.04±0.04 mm3)and unlikely to have caused significant ICP ***:This study provides evidence of an edema-independent ICP elevation following small ischemic stroke in *** occurrence of this rise supports our findings in other species and suggests it is caused by a previously undescribed mechanism.

关键词： cerebraledema intracranial pressure ischemic stroke

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Thermoluminescence characterization of natural and synthetic irradiated Ce-monazites

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journal of Rare earths 2024年第4期42卷 643-650页

作者： V.Correcher C.Boronat j.Garcia-Guinea j.F.Benavente T.Rivera-Montalvo CIeMAT Av.Complutense 4028040MadridSpain MNCN-CSIC J.Gutierrez Abascal 228006MadridSpain Instituto Politécnico Nacional CICATA-IPNAv.Legaria 694Mexico City11500Mexico

The thermoluminescence(TL)emission of synthetic and natural Ce-monazites was characterized here to determine the potential application in the identification of microscopic defects from a qualitative point of view trying to link each TL peak to a chemical-physical *** kinetic parameters that lead the luminescence processes were calculated by means of variable heating rate and computing glow curve deconvolution methods and allow identifying three groups of components at~90,130 and 290℃(for the mineral sample)and~90,170,220,270 and 320℃(for the synthetic CePO_(4):Nd_(0.20),La_(0.25)).The main differences appreciated in these complex TL curves are mainly due to(i)the content of impurities(natural sample contains lanthanides as well as U 0.60%and Th 5.22%)and(ii)the degree of crystallinity of the samples which is directly related to the type of impurities(synthetic monazite relies only on Nd and La).The behavior of the dose response in the range of 1-8 Gy is similar for both samples;the TL intensity increases linearly as the dose increases without changes in the position of the maxima,denoting first-order kinetic luminescence *** peak could be mostly associated with structural defects(i.e.,phase transitions),chemical reactions(i.e.,Ce3+?Ce4+redox reaction,dehydration or dehydroxylation processes)or intrinsic defects(i.e.,Frenkel defects,ODCs or NBOHCs).

关键词： Thermoluminescence Kineticparameters Phosphate Ce-monazite Defects Rare earths

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Study of the Physical and Mechanical Properties of Titanium in Volume by the MeAM Method

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Modeling and Numerical Simulation of Material Science 2024年第1期14卷 58-68页

作者： Yahnn j. Mighensle Mimboui Alain S. Dzabana Honguelet Timothée Nsongo Faculty of Science and Technology Marien Ngouabi University Brazzaville Congo Research Group on Physical and Chemical Properties of Materials Brazzaville Congo Association Alpha Sciences Beta Technologies Brazzaville Congo Geological and Mining Research Centre Brazzaville Congo

In this work we present the results of our study on the physical and mechanical properties of titanium in volume. The work consisted in determining its physical and mechanical properties under different crystallographic structures (HCP, FCC, BCC and SC) using the Modified embedded Atom Method (MeAM) and the MeAM potential of titanium. We used the LAMMPS calculation code, based on classical molecular dynamics, to determine the most stable structure of titanium, which is the hexagonal compact structure (HCP) with crystal parameters a = 2.952 Å and c = 4.821 Å and a cohesion energy of -4.87 eV. This structure is seconded by the cubic centred structure (BCC) with a lattice parameter a = 3.274 Å and a cohesive energy of -4.84 eV. It was shown that titanium can crystallise into a third structure which is the face-centred cubic (FCC) structure with a lattice parameter a = 4.143 Å and a cohesive energy of -4.82 eV. The results obtained in this study were compared with the theoretical results and showed considerable agreement.

关键词： MeAM Potential LAMMPS Code Molecular Dynamics elastic Constants Modules Ovito

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eLeCTRONIC STRUCTURe OF THe eLeMeNTS

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Chinese Physics C 2016年第10期40卷 124-125页

作者： j.e. Sansonetti NIST

The electronic configurations and the ionization energies are from the NIST database, ＂Ground Levels and Ionization energies for the Neutral Atoms,＂ W.C. Martin, A. Musgrove, S. Kotochigova, and j.e. Sansonetti, http：//*** .gov/pml/data/ion_energy. cfm. The electron configuration for, say, iron indicates an argon electronic core （see argon） plus six 3d electrons and two 4s electrons.

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《耳鸣患者皮层和皮层下听觉区超高场MRI的研究》摘译

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听力学及言语疾病杂志 2024年第4期32卷 384-385页

作者：申丽君文之(摘译) 曹永茂(审校) Berlot e Arts R Smit j 武汉大学人民医院耳鼻咽喉头颈外科武汉430060 武汉大学人民医院放射科

耳鸣研究的难点之一在于难以将耳鸣感知与其他合并症进行区分,例如听力损失和声音耐受性降低(DST)经常同时出现。在研究耳鸣动物模型时,区分起来尤其困难。对耳鸣患者研究时往往未能充分控制混杂因素。最近的研究表明,在仔细控制听力损... 详细信息

耳鸣研究的难点之一在于难以将耳鸣感知与其他合并症进行区分,例如听力损失和声音耐受性降低(DST)经常同时出现。在研究耳鸣动物模型时,区分起来尤其困难。对耳鸣患者研究时往往未能充分控制混杂因素。最近的研究表明,在仔细控制听力损失和DST后,耳鸣组和对照组之间先前存在的差异消失了。另一个难点是非侵入性测量技术的空间分辨率有限。为了检测诸如内侧膝状体(MGB)和下丘(IC)等皮层下听觉结构的频率响应特异性,需要高空间分辨率。由于这些结构仅为几立方毫米(例如内侧膝状体为4 mm×5 mm×4.5 mm),常规磁场(3T及以下)下的功能磁共振成像(fMRI)的空间分辨率为2 mm×2 mm×2 mm,无法检查这些微小结构中频率响应的特异性。7T的超高场(UHF)磁共振成像(MRI)提供的灵敏度有足够的分辨率显示微小的听觉皮层下结构的响应,便于详细描述其频率拓扑。本实验研究旨在UHF-MRI应用于耳鸣患者探索耳鸣的机制。

关键词：内侧膝状体立方毫米耳鸣患者混杂因素听力损失皮层下高空间分辨率动物模型

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europium recovery process by means of polymeric nanoparticles functionalized with acrylic acid,curcumin and fumaramide

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journal of Rare earths 2024年第10期42卷 1950-1959页

作者： P.A.Martínez-Montoya j.M.del Río A.de j.Morales-Ramirez M.Corea escuela Superior de Ingeniería Química e Industrias extractivas ESIQIE-IPNDepartamento de Ingeniería Metalúrgica UPALM S/N Col.Lindavista escuela Superior de Ingenieria Química e Industrias extractivas ESIQIE-IPNLaboratorio de Investigación en Polímeros y NanomaterialesUPALM S/N Col.Lindavista Centra de Investigación e Innovación Tecnológica CIITEC-IPNCda.de CECATIs/n

Polymeric nanoparticles of poly(methyl methacrylate) were obtained by emulsion polymerization techniques in a proce ss of two *** particles were functionalized with acrylic acid,curcumin,and fumaramide and three series of polymeric particles were *** incorporation of functional groups was confirmed by Fourier transform-infrared spectrosocopy(FT-IR) and ultraviolet-visible(UV-Vis) *** spherical morphology of particles with an average diameter of 100 nm was observed by scartning electron microscopy(SeM).The polymeric materials were used for recovery of [eu]from synthetic *** nanoparticles show excellent chelation capacity to trap rare-earth ions,because they recover more than 85% of [eu] at pH of *** images of SeM after extraction process show arrays between particles with larger average particle sizes to 1.5 *** addition,the particles have a good stripping capacity,exceeding 50% of it,maintaining their homogeneity in morphology and good stability in dispersion for the recovery and stripping processes.A pseudo-second model order is obtained for the extraction and stripping processes while the best results of stripping process are obtained at pH of6.

关键词： Chelating effect emulsion polymerization extraction process Rare earths Stripping process [eu]recovery

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Recent Ventures in Interdisciplinary Arctic Research:The ARCPATH Project

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Advances in Atmospheric Sciences 2024年第8期41卷 1559-1568页

作者： Astrid e.j.OGILVIe Leslie A.KING Noel KeeNLYSIDe François COUNILLON Brynhildur DAVIÐSDÓTTIR Níels eINARSSON Sergey GULeV Ke FAN Torben KOeNIGK james R.MCGOODWIN Marianne H.RASMUSSON Shuting YANG Institute of Arctic and Alpine Research(INSTAAR) University of ColoradoBoulder CO 80303USA Stefansson Arctic Institute AkureyriÍS-600Iceland Royal Roads University BC V9B 5Y2Canada University of Bergen Bergen N-5007Norway Nansen environmental and Remote Sensing Centre Bergen N-5007Norway University of Iceland Reykjavík 102Iceland Shirshov Institute of Oceanology Moscow 117218Russia Moscow State University Moscow 11991Russia Chinese Academy of Sciences Beijing 100045China Swedish Meteorological and Hydrological Institute SE-60176 NorrköpingSweden Danish Meteorological Institute CopenhagenØ2100Denmark Obukhov Institute of Atmospheric Physics RAS119017MoscowRussia

This paper celebrates Professor Yongqi GAO's significant achievement in the field of interdisciplinary studies within the context of his final research project Arctic Climate Predictions: Pathways to Resilient Sustainable Societies-ARCPATH(https://***/en/projects/finished-projects/arcpath). The disciplines represented in the project are related to climatology, anthropology, marine biology, economics, and the broad spectrum of social-ecological studies. Team members were drawn from the Nordic countries, Russia, China, the United States, and Canada. The project was transdisciplinary as well as interdisciplinary as it included collaboration with local knowledge holders. ARCPATH made significant contributions to Arctic research through an improved understanding of the mechanisms that drive climate variability in the Arctic. In tandem with this research, a combination of historical investigations and social, economic, and marine biological fieldwork was carried out for the project study areas of Iceland, Greenland, Norway, and the surrounding seas, with a focus on the joint use of ocean and sea-ice data as well as social-ecological drivers. ARCPATH was able to provide an improved framework for predicting the near-term variation of Arctic climate on spatial scales relevant to society, as well as evaluating possible related changes in socioeconomic realms. In summary, through the integration of information from several different disciplines and research approaches, ARCPATH served to create new and valuable knowledge on crucial issues, thus providing new pathways to action for Arctic communities.

关键词： Recent Ventures in Interdisciplinary Arctic Research:The ARCPATH Project

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Frequency-dependent viscoelasticity effects on the wave attenuation performance of multi-layered periodic foundations

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Applied Mathematics and Mechanics(english edition) 2024年第3期45卷 407-424页

作者： M.SAFI M.VAKILIFARD M.j.MAHMOODI Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of Mechanical and energy engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are numerically examined for their responses to longitudinal and transverse modes in the time and frequency *** different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,comprising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber materials,respectively,are taken into ***,the viscoelasticity behavior of the rubber is modeled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss *** the extraction of the complex dispersion curves and the identification of the band gaps(BGs),the simulations of wave transmission in the time and frequency domains are performed using the COMSOL *** parametric studies evaluate the effects of the rubber viscoelasticity models on the dispersion curves and the wave transmission for the longitudinal and transverse *** results show that considering the rubber viscoelasticity enhances the wave attenuation ***,the transverse-mode damping is more sensitive to the viscoelasticity model than its longitudinal *** 6-layer unit-cell LPF exhibits the lowest BG,ranging from 4.8 Hz to 6.5 Hz.

关键词： layered metamaterial periodic foundation complex dispersion curve wave transmission diagram

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